Recirculating systems are very common in hydroponics, some nutrient vendors even offer schedules to do so. It usually is a lower PPM than DTW. I am using it right now on my solo cup grow, but I have a 12 gallon reservoir feeding 1 dinky plant. I top off with just water.
It will be a learning curve for sure with a lot of plants feeding at the same time. You really do not know what the plants are using but can guess that it is a lot of N in veg and a lot of P-K in early to mid flower and less of everything in late flower. I would not want to see a drop of more than 100PPM without a res change.